Dropbox Installer 2.1.0 for ReadyNAS OS 4.x (x86)

While updating the Dropbox Manager for ReadyNAS OS 6 I also changed the way available Dropbox versions are detected. Since the new system should be more reliable and also detect versions that aren’t announced in the changelog by Dropbox I thought I’d better make that system available for ReadyNAS OS 4 systems as well. So here we go: